1. Field of the Invention
This invention relates to hydrogen bond stabilized surface modifying agents (HB-SMAs), surfaces treated with the agents, methods for treating surfaces to impart non-wettable, non-stick, friction-reducing, corrosion resistant, or other properties to the surfaces and methods for making the agents.
More particularly, the present invention relates to hydrogen bond stabilized surface modifying agents where the stability results from intermolecular hydrogen bonding between adjacent surface modifying agents, surfaces treated with the agents, methods for treating surfaces and methods for making the hydrogen bond stabilized surface modifying agents of this invention.
2. Description of the Related Art
The synthesis of long chain xcex1,xcfx89-functionalized semi-fluorinated hydrocarbons, where xcex1 and xcfx89 are integers that describe the positions of specific functional groups along the fluorohydrocarbon backbone, remains a challenging enterprise for interfacial scientists. The generation of organized thin films from these molecules offers the opportunity to study and manipulate fundamental properties of fluorinated interfaces, such as wetting, adhesion, and tribology. The ability to control the identities of the xcex1,xcfx89-functionalities using organic synthesis permits atomic-level control over the structure and composition of interfaces formed from these molecules using self-assembly techniques. Organic synthesis thus provides a convenient tool for fine-tuning the interfacial properties.
Several methods have been utilized for the preparation of compounds having perfluorinated terminal segments.1-6 Many approaches have been designed to yield target molecules containing a terminal CF3 group.7-16 A limited number ofmethods have, however, provided the opportunity to introduce fluorinated segments of differing lengths.
Brace, for example, investigated the radical addition of several iodoperfluorinates to allylacetate.1,2 This approach was based on initial studies by Park and Lacher17 and Moore,18 which utilized ultraviolet light as the radical source. By employing an azo initiator, however, Brace was able to complete the reaction within a few hours compared to five days when using UV light. Brace and previous investigators19,20 proposed that the reaction proceeded through the formation of a perfluoroalkyl radical that attacked the terminal carbon of the olefinic group. Reduction of the resultant fluorinated iodoacetate with zinc or LiA1H4 provided a variety of perfluoroalkylated compounds in excellent yields.2 
Cloux and Kovats modified the approach developed by Brace to include the addition of2,2,2-trifluoroethyl iodide to terminal alkenes.21 2,2,2-Trifluoroethyl iodide is a liquid and made handling the reaction easier than the reaction using gaseous trifluoromethyl iodide. The authors noted that microanalyses failed to give correct and reproducible results.
Several groups have shown that thiol-terminated reagents can be used to modify the interfacial properties of metallic surfaces due to the strong interaction between the thiol moiety and the metal atoms of the surface.22-24 Other related strategies for modifying the properties of both metallic and non-metallic surfaces are also known.22-24 
Although the radical coupling of T-alkenyl acetates with xe2x80x3-halo-fluorinated hydrocarbons has been reported, and surface modification strategies involving intermolecular H-bonded hydrocarbon adsorbates have been reported,25 there still exists a need in the industry for a cost effective, high yield and versatile method for making fluorinated surface modifying agents (e.g., fluorinated alkanethiols or disulfides) and their precursors that can be used to control surface characteristics, imparting, for example, corrosion-resistant, non-wettable, non-stick, or low frictional properties to the surfaces.
The present invention provides hydrogen bond stabilized surface modifying agents (HB-SMAs) including at least one fluorine and carbon-containing tail group, at least one surface reactive head group and at least one hydrogen bonding group interposed between the head and tail groups. The surface modifying agents are used to coat metallic, ceramic or other surfaces to influence, change, augment or enhance the surface characteristics of the material.
The present invention provides HB-SMAs represented by Formula (I):
(Rf)xcex1xe2x88x92"khgr"xe2x88x92(Q)xcex2xe2x80x83xe2x80x83(I) 
where:
Rf is a carbon-containing head group including at least one fluorine atom;
"khgr" is a carbon-containing group including at least one moiety or functional group capable of intermolecular hydrogen bonding or related acid-base interaction;
Q is a tail group including at least a N atom, an O atom, a Si atom, a P atom or a S atom;
xcex1 and xcex2 are integers the sum of which does not exceed the maximum number of substituents "khgr" can accomodate. "khgr" can further include a multivalent moiety Rxe2x80x3, where Rxe2x80x3 is a tetravalent atom, carbon-carbon double bond or a ring system.
The present invention provides a preferred class ofHB-SMAs represented by Formula (III):
Rf"khgr"xe2x88x92Q xe2x80x83xe2x80x83(III) 
where Rf, "khgr" and Q are as previously defined.
The present invention also provides a preferred class of HB-SMAs represented by Formula (III) where Rf is as previously defined and where:
"khgr" is RHB, R1xe2x88x92RHB,RHBxe2x88x92R1, R1xe2x88x92RHBxe2x88x92RXL,RHBxe2x88x92R1xe2x88x92RXL,RHBxe2x88x92RXLxe2x88x92R1,R1xe2x88x92RXLxe2x88x92RHB,
RXLxe2x88x92R1xe2x88x92RHB, RXLxe2x88x92RHBxe2x88x92R1, R1xe2x88x92RHBxe2x88x92R2, R1xe2x88x92RHBxe2x88x92R2xe2x88x92RXL, RHBxe2x88x92R1xe2x88x92RXLxe2x88x92R2, 
R1xe2x88x92RXLxe2x88x92R2xe2x88x92RHB, RXLxe2x88x92R1xe2x88x92RHBxe2x88x92R2, or combinations or mixtures thereof, where:
R1 and R2 are the same or different and are carbon-containing groups;
RHB is a group including a peptide linkage (xe2x80x94C(O)N(H)xe2x80x94), urethane linkage (xe2x80x94Oxe2x80x94C(O)xe2x80x94N(H)xe2x80x94), urea linkage (xe2x80x94N(H)xe2x80x94C(O)xe2x80x94N(H)xe2x80x94) or mixtures or combination thereof; and
RXL is a crosslinkable group including an acetylenic group, a diacetylenic group, polyacetylenic group, an alpha amino acid group, an alpha hydroxy acid group or a dialkoxysilenyl group; and
Q is NR3, OR3, SiR3, SiOR3, PR3, SR3 or CE1E2, where:
R3 is a hydrogen atom or a carbon containing group, and
E1 is NR4, O, PR4 or S,
E2 is R4, NR42, OR4, PR42, or SR4; and where:
each R4 is the same or different and is a hydrogen atom or a carbon-containing group.
The present invention also provides a dimeric HB-SMAs of Formula (IV):
Rfxe2x88x92"khgr"xe2x88x92QQxe2x80x2xe2x88x92"khgr"xe2x80x2Rfxe2x80x2xe2x80x83xe2x80x83(IV) 
where Rf and Rfxe2x80x2, R and Rxe2x80x2, "khgr" and "khgr"xe2x80x2 and Q and Qxe2x80x2 are the same or different groups as defined previously.
This invention also provides methods for making HB-SMAs of Formulas (I-IV).
This invention also provides a method for treating surfaces of substrates including contacting the substrate or substrate surface(s) with at least one agent of Formulas (I-IV) in an amount sufficient to form a partial or complete monolayer of the agent thereon.
This invention also provides a method for treating a surface including contacting a surface with at least one agent of Formulas (I-IV) to form a partial or complete monolayer of the agent thereon.
The present invention also provides a substrate including a surface having a partial or complete monolayer formed of at least one agent of Formulas (I-IV).
The present invention also provides devices or apparatus incorporating a substrate including a surface having a partial or complete monolayer formed of at least one agent of Formulas (I-IV).